Testing Object Type

is_NA tests if a variable is exactly NA (logical, character, numeric or integer)

isFALSE Tests if a variable is exactly FALSE.

isNumber tests if a variable is a single number

isReal tests if a variable is a single real number

isInteger tests if an object is a single integer

isString tests if an object is a character string.

is.dir tests if a filename is a directory.

is.file tests if a filename is a file.

hasNames tests if an object has names.

is_NA(x)

isFALSE(x)

isNumber(x)

isReal(x)

isInteger(x)

isString(x, y, ignore.case = FALSE)

is.dir(x)

is.file(x)

hasNames(x, all = FALSE)

Arguments

x	an R object
y	character string to compare with.
ignore.case	logical that indicates if the comparison should be case sensistive.
all	logical that indicates if the object needs all names non empty

TRUE or FALSE